Cancerous lymph nodes may feel rubbery and clumped together in the case of lymphomas or hard and immobile in the case of metastatic cancers, according to the Merck Manual Home Edition. In both cases, the lymph nodes are swollen but painless when touched.
Cancerous lymph nodes are usually associated with other symptoms, states MedicineNet. These symptoms include fevers, persistent fatigue, night sweats and significant, unexplained weight loss. The night sweats associated with cancer are described as "soaking" and require the changing of bed clothes and sheets. Unexplained weight loss in excess of 10 percent of a patient's body weight, with or without a loss of appetite, also needs prompt evaluation by a doctor. Fevers may or may not have a definitive pattern.
Swollen lymph nodes rarely indicate cancer, according to the Merck Manual Home Edition. In fact, among those patients who present with enlarged lymph nodes, less than 1 percent have cancer. Infections are the most common cause of swollen lymph nodes, particularly upper respiratory infections and infections in the tissues close to the affected nodes. Other more serious infections, such as tuberculosis and HIV, can cause enlarged lymph nodes as can autoimmune diseases, such as lupus or rheumatoid arthritis.